Roll bar portion of a helmet



FIG. 1 is a perspective view of a first embodiment of a roll bar portion of a helmet showing our new design;

FIG. 2 is a front orthographic view thereof;

FIG. 3 is a left side orthographic view thereof;

FIG. 4 is a right side orthographic view thereof; and,

FIG. 5 is a top orthographic view thereof.

The dashed lines shown in FIGS. 1–5 are included for the purpose of illustrating environmental elements only and form no part of the claimed design. The dotted lines shown in FIGS. 1–5 define a border between claimed and unclaimed subject matter and form no part of the claimed design. The bottom view is omitted and forms no part of the claimed design. 

The ornamental design for a roll bar portion of a helmet, as shown and described. 